Means for igniting a gaseous fuel burner



Nov. 30, 1965 N. L. HULTGREN ET AL 3,220,452

MEANS FOR IGNITING A GASEOUS FUEL BURNER Filed March 19, 1963 2 Sheets-Sheet 1 FIG.

a J 25 a %526/7/ 9 4 33 47 FIG. 2

WffdP/Vf/ Nov. 30, 1965 N. 1... HULTGREN ET AL 3,220,462

MEANS FOR IGNITING A GASEOUS FUEL BURNER Filed March 19, 1963 2 Sheets-Sheet 2 FIG. 3

United States Patent 3,220,462 MEANS FOR IGNITXNG A GASEOUS FUEL BURNER Niis Lennart Hultgren and Alie John Eriicsson, Stockholm,

Sweden, assignors to Aktiebolaget Eiectrolux, Stockholm, Sweden, a corporation of Sweden Filed Mar. 19, 1963, Ser. No. 266,373 (liaims priority, application Sweden, Mar. 23, 1962, 3,309/62 Claims. (Cl. 158-130) Our invention relates to means for igniting a gaseous fuel burner at a region removed therefrom and to which flow of gaseous fuel is interrupted by control apparatus when the burner flame is extinguished.

It is an object of our invention to provide for a gaseous fuel burner having control apparatus of this type a flash-back ignition tube which is movable between inoperative and operative positions and in its operative position can be employed to ignite the burner at a region removed therefrom when a main valve member in the path of flow of gaseous fuel is manually moved from a flow preventing position to a flow-permitting position.

Further objects and advantages of our invention will become apparent from the following description and accompanying drawings forming a part of this specification, and of which FIG. 1 is a vertical sectional view of a household refrigerator provided with burner equipment embodying our invention; FIG. 2 is an enlarged vertical view, partly in section, illustrating the burner equipment shown in FIG. 1; and FIGS. 3 and 4 are views similar to FIG. 2 illustrating parts of the burner equipment in different positions from the one shown in FIG. 2.

Referring to FIG. 1, we have shown our invention in connection with a household refrigerator including a cabinet 10 having thermally insulated walls 11 defining a storage compartment 12 into which access may be gained by a door 14 hinged to the front of the cabinet. Within the storage compartment 12 is disposed a cooling element or evaporator 15 of suitable refrigeration apparatus. Although we do not wish to be limited thereto, the refrigeration apparatus may be of a uniform pressure absorption type, generally as described in Patent No. 2,956,415 to W. G. Kogel. In refrigeration apparatus of this type, the cooling element 15 is connected to other parts, including a generator 16, which are mounted in the cabinet 10 and positioned in a vertically extending space 17 at the rear of the cabinet. In order to simplify the drawing, only the generator 16 has been shown in rear apparatus space 17 of FIG. 1, an illustration of the other parts of the refrigeration apparatus not being necessary for an understanding of our invention.

The generator 16, which constitutes the heat receiving part of the refrigeration apparatus, includes an outer shell 18 through which extends a heating flue 19, the lower end of which projects below the bottom of the shell into the rear part of a space 21) below the storage compartment 12, which is accessible through an opening 21 at the front of the cabinet 16 adapted to be closed by a removable closure member or hinged door (not shown). The heating flue 19 is provided with a riser or flue extension 22 which extends upward in the rear apparatus space 17 and is mounted in position in any suitable manner. The upper end of the riser 22 may be flush with an apertured member 23 so that natural circulation of air may take place in the rear apparatus space 17 to promote cooling of parts of the refrigeration apparatus. Although not essential, the rear apparatus space 17 may be provided wit-h a rear cover plate 24.

The refrigeration apparatus is operated by a gaseous fuel which is delivered from a suitable source of supply through conduits 25 and 26 and valve units 27, 28 and 29 to a burner 31 which is positioned at the rear of the space 20 and arranged to discharge its flame into the lower end of the heating flue 19 The burner is fixed to the lower end of an upright pin 31, the upper end of which is secured to an apertured plate 32 adapted to be removably secured to the bottom of the generator shell 18.

The valve unit 27 is provided with an operating handle 27a for manually controlling flow of gaseous fuel to the burner 31 During operation of the refrigeration apparatus, the valve unit 27 normally remains in its open position. The valve unit 28 is thermostatically controlled and is provided with a capillary tube 33 and thermal sensitive bulb 34 adapted to contain a suitable volatile fluid, the bulb 34 being arranged in the space 12, for example, as seen in FIG. 1. The valve unit 28 functions to control flow of gaseous fuel to the burner 30 responsive to a temperature condition affected by the cooling element 15 and may be provided with a control knob 28a to adjust the temperature at which it is desired to maintain the space 12. In both FIGS. 1 and 2 it will be seen that the control knob 28a is easily accessible at the front opening 21 of the space 20 beneath the door 14 of the cabinet 10.

The burner 30 includes a base 35 having a passage connected to receive gaseous fuel from the conduit 26. Gaseous fuel is discharged from the base 35 through an orifice member 36 to which is secured an upright tube 37 having ports 38 through which primary air is drawn into the tube where it mixes with the gaseous fuel to provide a gas mixture. The combustible gas mixture flows upward through the tube 37 and issues through a discharge port 39 at its upper end at which region the gas mixture is ignited and the burner flame is maintained. About the upper part of the tube 37, at a region above the ports 38, is provided a hollow sleeve 40, which defines a ring-shaped passage 41 closed at its lower end. The hollow sleeve extends upward about the tube 37 and its upper open end 42 is at a level above the discharge port 39. A part of the gas mixture in the tube 37 flows through ports 43 therein into the lower end of the passage 41, the gas mixture diverted into the passage 41 flowing upward therein and issuing therefrom at its upper open end 42. It will now be understood the fuel burner 30 has a single port 42 from which gaseous fuel is discharged vertically upward. With this construction, a single flame is produced at the upper open end or discharge port 42 of the hollow sleeve 40.

The valve unit 29 comprises a casing 44 having a valve member 45 which is movable toward and from a valve seat 46 interposed between the gaseous fuel inlet and outlet 47 and 48, respectively. When the valve member 45 is in intimate physical contact with the valve seat 46, the valve member is in flow-preventing position and the flow of gaseous fuel to the burner 30 is shut off; and when the valve member 45 is moved to a position removed from the valve seat 46, the valve member is in flow-permitting position and gaseous fuel can flow to the burner 30.

An electromagnet 49 is provided at the fuel inlet side of the valve seat 46 to hold the valve member 45 in flow-permitting position. The electromagnet 49 includes an armature 5t fixed to and movable with the valve member 45 and an energizing coil or winding 51 having its opposite ends connected by conductors 52 and 53 to a thermoelectric generator 54. A coil spring 55 is disposed between the valve member 45 and inwardly extending flange 56 within the casing 44 and biases the valve member to its flow-preventing position against the valve seat 46. The electromagnet 49 when activated or energized functions to hold the armature 50 and valve member 45 in the flow-permitting position shown in FIG. 4, the armature and valve member being moved to this position against the bias of the coil spring 55. The electromagnet 49 when energized is not capable of moving the valve member 45 from its flow-preventing position in FIG. 2 to its flow-permitting position in FIG. 4, but is capable of holding the valve member 45 in its flow-permitting position in FIG. 4 after being moved thereto in a manner which will be described presently.

As seen in FIG. 2, one end of a rod or pin 57 bears against the valve member 45 to move the latter to flowpermitting position against the biasing action of the coil spring 55. The rod 57 extends through an opening in a cap screw 58 and is provided at its outer end with an operating member 59. A suitable packing 60 is provided about the rod at one end of a chamber 61 to prevent leakage of gaseous fuel through an opening 62 through which the rod extends. A coil spring 63 in [chamber 61 is disposed about the rod 57, one end of which bears against the packing 60 and the other end of which bears against a washer 64 fixed to the rod 57. The rod 57 is biased outward by the coil spring 63, and, when the operating member 59 is pushed inward, inward movement is imparted to the rod 57 against the biasing action of the spring 63.

The electromagnetically powered valve unit 29 functions to shut off the supply of gaseous fuel to the burner 30 when the burner flame is extinguished. To start the burner 30 the operating member 59 is pushed inward to move valve member 45 to its flow-permitting position. This permits gaseous fuel to flow through conduit 26 to burner 30. In the manner described above the combustible gas mixture formed in the burner 30 is discharged through the ports 39 and 42 at which region the gas mixture is ignited to provide the burner flame. The thermoelectric generator or thermocouple 54 is heated by the burner flame and produces a current which flows in the electric circuit including the conductors 52 and 53 and the coil 51 to energize the latter. When the coil 51 is energized the armature 50 and the valve member 45 are held in flow-permitting position against the bias of the spring 55. When this occurs the operating member 59 may be released and the valve member 45 will remain in flow-permitting position.

If for any reason the burner flame is extinguished, heating of the thermocouple 54 will stop and it is rendered inoperable to generate current. When this occurs the electromagnet 49 is inactivated or deenergized and the coil spring 55 will be effective to cause the valve member 45 to move to flow-preventing position against the valve seat 46 and shut off flow of fuel to the burner 30.

In accordance with our invention, we provide a flashback ignition tube 65, which is horizontally movable in apertured brackets 66, in the space 20 for igniting the burner 30 at front opening 21 of the cabinet when the valve member 45 of valve unit 29 is moved to its flow-permitting position. The end 65a of the hollow tube 65 at the vicinity of the burner 30, which may be referred to as its rear end, is formed with a fork-shaped part having parallel arms 67 extending past opposing sides of the burner tube 37. The arms 67 of the fork-shaped part project rearward from the bottom portion of the rear end 65a of the tube 65 and function as a guide for the tube when it is moved between a front inoperative position illustrated in FIGS. 2 and 4 and a rear operative position illustrated in FIG. 3. The rear end 65a of the tube 65 is also provided with an overhanging part or hood 68 which projects rearward only from the top portion of the tube and is curved downward and terminates at a level slightly above the upper end 42 of the burner sleeve 40.

In its front inoperative position the hood 68 of the flash-back ignition tube 65 is laterally offset from the single port 42 of the burner 30 and hence is out of the path of flow of the gas mixture discharged vertically upward from the burner port 42 and ineffective to disturb the flame adapted to be produced at the port 42 Hence, in its front inoperative position the burner flame, indicated at 30a in FIG. 4, is unobstructed by the hood 68 and the rear end 65a of the tube 65 and it projects toward the lower end of the heating flue 19.

In its rear operative position the hood 68 overlies the upper open end or port 42 of the burner 30 and the gas mixture discharged vertically upward from the burner port 42' is diverted into the rear end 650: of the tube 65 and flows therethrough to the front open end 65b of the tube. The gas mixture diverted into the tube 65 may be conveniently ignited at the front open end 65b of the tube, at the region of the front cabinet opening 21, and the resulting flame produced will flash back through the tube and ignite the gas mixture discharged from the burner port 42. It will now be understood that the flash-back tube 65 is mounted on the apertured brackets 66 for bodily movement in the direction of its length along a fixed horizontally extending line between its front inoperative position and its rear operative position. The tube 65 desirably is provided with a series of openings 65c which extend from the rear open end 650 to the front open end 65b thereof. By providing an adequate number of openings 650 of the proper size along the length of the tube 65, a sufficient quantity of air will pass through the openings to insure complete combustion of the gaseous fuel when the gas mixture is ignited at the front open end 65b, so that the flame produced at the front open end will flash back through the tube 65 and insure reliable starting of the burner 30.

The operating member 59 is connected by an upright member 69 to the front end of the tube 65. Hence, the tube 65 moves from its inoperative position to its operative position when the operating member 59 is pushed rearward to move the valve member 45 to flow-permitting position. When a flame is produced at the burner 30 by igniting the gas mixture diverted into the tube 65 after it has been moved to its operative position by pushing the operating member 59 rearward, the member 59 is held for an interval of time. During this time interval, the burner flame effects heating of the thermocouple 54 which produces a current to energize the electromagnet 49. This renders the electromagnet 49 operable to hold the valve member 45 in its flow-permitting position against the bias of spring 55. When this occurs the operating member 59 may be released and the coil spring 63 becomes effective to move the operating member 59 outward and also move the flashback ignition tube 65 forward to its inoperative position.

The armature 50 and valve member 45 fixed thereto are movable in a first range or distance between the flow-preventing and flow-permitting positions of the valve member while the flash-back ignition tube 65 is movable through a greater distance between its operative and inoperative positions. Accordingly, the rod 57 and coil spring 63 coact with the valve member 45 and tube 65 in such manner that the operating member 59 is manually movable through a second larger range between the positions shown in FIGS. 2 and 3 to move the valve member 45 through the shorter first range from flow-preventing to flow-permitting positions seen in FIGS. 2 and 3, respectively. This may be accomplished by providing a rod 57 of such length that the operating member 59 can be pushed inward for a given distance before the rod contacts the valve member 45 and commences to impart movement thereto. Before the rod 57 contacts the valve member 45 it is dissociated from the valve member when the latter is in its flow-preventing position. Also, a coil spring 70 may be arranged in the recess 71 formed in the operating member 59, the spring being disposed between the bottom of the recess and the end of the rod 57 which extends into the recess. With this arrangement the operating member 59 can be pushed inward for a given distance against the spring 70 before rod 57 commences to move inward. With this construction the tube 65 can move from its inoperative position to its operative position in a range corresponding to the second larger range of the operating member 59.

Although We have shown and described a particular embodiment of our invention, we do not wish our invention to be limited to the particular arrangement set forth, and we intend in the following claims to cover all modifications which do not depart from the spirit and scope of our invention.

We claim:

1. In apparatus of the class described having a gaseous fuel burner and means forming a path of flow of gaseous fuel thereto, valve means in the path of flow, the valve means being biased to flow-preventing position and movable to flow-permitting position with respect to gaseous fuel flow, the combination of an elongated flash-back tube having a first opening at one end thereof and a second opening at the opposite end thereof at which the burner is adapted to be ignited, mounting means for mounting the flash-back tube for movement bodily in the direction of its length along a fixed horizontally extending line, the tube being bodily movable on the mounting means along the line between an inoperative position and an operative position in which the first opening at the one end of the tube is adapted to receive gaseous fuel discharged from the burner when the valve means is moved to its flow-permitting position whereby, when the gaseous fuel received by the tube at the first opening at the one end thereof is ignited at the second opening at the opposite end thereof, the flame produced will flash back through the tube to ignite the gaseous fuel at the burner, and the flash-back tube in its inoperative position being ineffective to receive at the first opening at the one end thereof gaseous fuel discharged from the burner when the valve means is moved to its flow-permitting position.

2. In apparatus as set forth in claim 1 in which the gaseous fuel burner has a single port from which gaseous fuel is discharged vertically upward, the combination further including an overhanging part which extends horizontally beyond the one end of the tube only from the upper portion thereof to form a hood, the hood overlying the single port of the burner in the operative position of the tube to promote flow of gaseous fuel from the burner to the first opening at the one end of the tube when said valve means is moved to its flow-permitting position, and the hood in the inoperative position of the tube being laterally offset from the single port of the burner and ineffective to disturb the flame adapted to be produced at the single port of the burner.

3. Apparatus as set forth in claim 1 which includes means for biasing the tube to the inoperative position, the tube being bodily movable in the direction of its length against the action of the biasing means.

4. Apparatus as set forth in claim 1 which includes means operable when the valve means is moved to its flow-permitting position for moving the tube bodily in the direction of its length from its inoperative position to its operative position.

5. In apparatus of the class described having a gaseous fuel burner and means forming a path of flow of gaseous fuel thereto, valve means in the path of flow, the valve means being biased to flow-preventing position and movable to flow-permitting position with respect to gaseous fuel flow, the combination of a manually movable member cooperable with the valve means and biased from the latter, the manually movable member being movable against its bias to move the valve means from its flowpreventing position to its flow-permitting position, an elongated flash-back tube having a first opening at One end thereof and a second opening at the opposite end thereof at which the burner is adapted to be ignited,

Mounting means for mounting the flash-back tube for movement bodily in the direction of its length along a fixed horizontally extending line, the tube being bodily movable on the mounting means along the line between an inoperative position and an operative position in which the first opening at the one end of the tube is adapted to receive gaseous fuel discharged from the burner when the valve means is moved to its flow-permitting position by the manually movable member whereby, when the gaseous fuel received by the tube at the first opening at the one end thereof is ignited at the second opening at the opposite end thereof, the flame produced will flash back through the tube to ignite the gaseous fuel at the burner, and the flash-back tube in its inoperative position being ineffective to receive at the first opening at the one end thereof gaseous fuel discharged from the burner when the valve means is moved to its flow-permitting position.

6. Apparatus as set forth in claim 5 which includes means operable when the valve means is moved to its flow-permitting position by the manually movable member for moving the tube bodily in the direction of its length from its inoperative position to its operative position.

7. Apparatus as set forth in claim 5 including means operatively connecting the tube and the manually movable member whereby the manually movable member functions to bias the tube to its inoperative position and simultaneously move the valve means to its flow-permitting position and the tube to its operative position when movement is imparted thereto.

8. Apparatus as set forth in claim 7 in which the valve means is movable in a first range between its flow-preventing and flow-permitting positions, and the manually movable member in its biased position is dissociated from the valve means when the latter is in its flow-preventing position and movable in a larger second range between its biased position and its functioning position to render it operable to move the valve means to its flow-permitting position, the tube between its operative and inoperative positions being movable in a range corresponding to said second larger range.

9. Apparatus as set forth in claim 5 in which the tube is biased to the inoperative position and movable to the operable position when the valve means is moved to its flow-permitting position by the movable member.

10. In apparatus of the class described having a gaseous fuel burner and means forming a path of flow of gaseous fuel thereto, valve means in the path of flow, the valve means being biased to flow-preventing position and movable to flow-permitting position with respect to gaseous fuel flow, holding means operable when activated to hold the valve means in flow-permitting position when moved thereto, means coacting with the holding means and adapted to be responsive to the heat of gaseous fuel burned at the burner for actuating the holding means in response to burning of the fuel and for inactivating the holding means in response to extinction of the burner, the combination of an elongated flash-back tube having a first opening at one end thereof and a second opening at the opposite end thereof at which the burner is adapted to be ignited, mounting means for mounting the flashback tube for movement bodily in the direction of its length along a fixed horizontally extending line, the tube being bodily movable on the mounting means along the line between an inoperative position and an operative position in which the first opening at the one end of the tube is adapted to receive gaseous fuel discharged from the burner when the valve means is moved to its flowpermitting position whereby, when the gaseous fuel received by the tube at the first opening at the one end thereof is ignited at the second opening at the opposite end thereof, the flame produced will flash back through the tube to ignite the gaseous fuel at the burner, and the flash-back tube in its inoperative position being ineffective to receive at the first opening at the one end thereof gaseous fuel discharged from the burner when the valve means is moved to its flow-permitting position.

References Cited by the Examiner UNITED STATES PATENTS Masoner 158-115 Betz 158-130 Dobler 158-115 Hollman 158-130 FREDERICK L. MATTESON, JR., Primary Examiner.

MEYER PERLIN, JAMES W. WESTHAVER,

Examiners. 

1. IN APPARATUS OF THE CLASS DESCRIBED HAVING A GASEOUS FUEL BURNER AND MEANS FORMING A PATH OF FLOW OF GASEOUS FUEL THERETO, VALVE MEANS IN THE PATH OF FLOW, THE VALVE MEANS BEING BIASED TO FLOW-PREVENTING POSITION AND MOVABLE TO FLOW-PERMITTING POSITION WITH RESPECT TO GASEOUS FUEL FLOW, THE COMBINATION OF AN ELONGATED FLASH-BACK TUBE HAVING A FIRST OPENING AT ONE END THEREOF AND A SECOND OPENING AT THE OPPOSITE END THEREOF AT WHICH THE BURNER IS ADAPTED TO BE IGNITED, MOUNTING MEANS FOR MOUNTING THE FLASH-BACK TUBE FOR MOVEMENT BODILY IN THE DIRECTION OF ITS LENGTH ALONG A FIXED HORIZONTALLY EXTENDING LINE, THE TUBE BEING BODILY MOVABLE ON THE MOUNTING MEANS ALONG THE LINE BETWEEN AN INOPERATIVE POSITION AND AN OPERATIVE POSITION IN WHICH THE FIRST OPENING AT THE ONE END OF THE TUBE IS ADAPTED TO RECEIVE GASEOUS FUEL DISCHARGED FROM THE BURNER WHEN THE VALVE MEANS IS MOVED TO ITS FLOW-PERMITTING POSITION WHEREBY, WHEN THE GASEOUS FUEL RECEIVED BY THE TUBE AT THE FIRST OPENING AT THE ONE END THEREOF IS IGNITED AT THE SECOND OPENING AT THE OPPOSITE END THEREOF, THE FLAME PRODUCED WILL FLASH BACK THROUGH THE TUBE TO IGNITE THE GASEOUS FUEL AT THE BURNER, AND THE FLASH-BACK TUBE IN ITS INOPERATIVE POSITION BEING INEFFECTIVE TO RECEIVE AT THE FIRST OPENING AT THE ONE END THEREOF GASEOUS FUEL DISCHARGED FROM THE BURNER WHEN THE VALVE MEANS IS MOVED TO ITS FLOW-PERMITTING POSITION. 